Emily HOWELLS

Type of support

Post-Doctoral Fellowship

Granted amount

120 000 €

Duration

2 years

Coral reefs support important, rich ecosystems today, but risk becoming a thing of the past as climate change causes the oceans to warm. That is, unless the corals in question are able to adapt to higher temperatures. These colonial animals, whose secreted skeletons form the structure of coral reefs, already live within a degree or two of their thermal limit. The exact threshold varies, though, even within a species and at a single location. This suggests corals have the capacity to adapt to higher temperatures, but will they do so fast enough to stay ahead of the 4°C increase predicted for the end of the century? Dr. Emily Howells is researching that question in the Arabian Gulf, home to the world’s hottest reefs. Here, some corals already live at 35-36°C, which is very near the temperature projected for other marine zones.Studies have shown certain wild populations are capable of increasing their thermal limit in just a few years, though no one knows quite how they do it. Dr. Howells is investigating the mechanisms underlying this phenomenon, testing whether an initial experience of heat stress can leave adult corals more tolerant in the future. In the lab, she will expose larval, juvenile and adult corals to different temperatures and measure how this affects their response to a subsequent thermal challenge. She will monitor this with physiological measurements, and determine how much is down to the corals’ genetic makeup versus the environmental heat exposure. Dr. Howells will also explore epigenetic changes to genes associated with heat tolerance. These affect the regulation of gene expression without changing the DNA sequence itself.Together, the results of Dr. Howells research could improve predictions of corals’ ability to adapt to warmer waters. If she finds that an initial exposure to high temperatures makes corals more resilient in a long-lasting or heritable way, coral nurseries could use this knowledge to raise more adaptable populations for the restoration of damaged reefs. This would be a boon for the thousands of species supported by coral reef ecosystems.

Scientific titles: The Importance Of Life Experiences In Shaping The Thermal Tolerance Of Reef Corals